DESPITE IMPROVEMENT IN THE CONTROL OF LOCAL DISEASE, DEVELOPMENT OF METASTASES, ESPECIALLY PULMONIC METASTASES, CONTINUES TO BE A CHALLENGING THERAPEUTIC PROBLEM IN SARCOMA PATIENTS. OUR HYPOTHESIS IS THAT RADIOLABELED ANTISARCOMA MONOCLONAL ANTIBODY MAY AID OR IMPROVE THE DETECTION OF SMALL OR OCCULT SARCOMATOUS DEPOSITS IN THESE PATIENTS. WE HAVE RECENTLY PRODUCED A MOUSE MONOCLONAL ANTIBODY (MAB 1924) WHICH IS BROADLY CROSS-REACTIVE WITH HUMAN SARCOMAS, AND HAVE ADMINISTERED IT TO ANIMALS AND PATIENTS WITHOUT SIGNIFICANT TOXIC EFFECTS. USING IMAGING TECHNIQUES WE HAVE DETECTED TUMOR DEPOSITS IN ANIMALS AND PATIENTS WHO RECEIVED THE RADIOLABELED ANTIBODY. THE SMALLEST HUMAN TUMOR DETECTED MEASURED 1.5 1.0 0.5 CM. MOST RECENTLY WE HAVE DETECTED RIGHT LOWER LUNG METASTASES AND IN TWO PATIENTS DIAGNOSIS WAS MADE EXCLUSIVELY BY ANTIBODY SCAN. FURTHERMORE, GAMMA COUNTER ANALYSIS OF OPERATIVE SPECIMENS HAS CONSISTENTLY SHOWN INCREASED RADIOACTIVITY IN TUMOR DEPOSITS. THE SPECIFIC AIMS OF THIS RESEARCH ARE: 1.TO DETERMINE OPTIMAL CONDITIONS FOR SARCOMA IMAGING IN AN ANIMAL SYSTEM AND IN PATIENTS USING MONOCLONAL ANTIBODY 19-24 LABELED WITH 125I, 131I AND 111IN; 2.TO USE THE SELECTED OPTIMAL FORM OF ANTIBODY 19-24 AND RADIOLABEL TO DETERMINE IF SMALL TUMOR FOCI (E.G., 1-2 CM PULMONIC METASTASES) IN SARCOMA PATIENTS CAN BE SUCCESSFULLY IMAGED. THE LONG-RANGE GOALS FOR THIS RESEARCH INCLUDE THE USE OF VARIOUS ANTISARCOMA ANTIBODIES IN DIAGNOSIS, FOLLOWUP AND THERAPY OF SARCOMA PATIENTS. THESE AIMS WILL BE ACCOMPLISHED THROUGH THE COMBINED EFFORTS OF MEDALEASE, INC., AND THE RESOURCES OF THE